The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 27, 1984
Filed:
Jan. 19, 1983
Applicant:
Inventor:
Kenneth L Parks, Plant City, FL (US);
Assignee:
Agrico Chemical Company, Tulsa, OK (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C01B / ; C01F / ; C01F / ;
U.S. Cl.
CPC ...
423317 ; 423320 ; 4233 / ; 423166 ; 423555 ;
Abstract
A process for the improved filterability of wet process phosphoric acid which comprises maintaining the ratio of ferric ion to ferrous ion in the wet process phosphoric acid above about 1.0 when the total iron concentration of the product wet process phosphoric acid is in the range of from about 0.5% Fe to about 0.9% Fe. The ratio of ferric ion to ferrous ion may be controlled by controlling the temperature in the final stage of a multi-stage calcining process, addition of iron in the form of a compound which yields ferric ion upon dissolution, the oxidation of the iron in the wet process phosphoric acid, or a combination of the above.